In all the presidential primaries so far, national convention delegates have been awarded according to inscrutable formulae, such as the one in Nevada which awarded Obama more delegates though Clinton won a majority of the popular vote. That changes next week.
Florida's primary, on January 29th, is winner-take-all and awards 57 Republican convention delegates. Winner-take-all isn't really winner-take all: in Florida, like Michigan and others, the winner of the state gets a bundle of statewide delegates, but district delegates are also awarded. The current leader in delegates is Romney with 59; Huckabee has 40 in second place and McCain 36. With a win in Florida, any of these candidates could become a bona fide front-runner.
Right now, InTrade political securities have McCain Florida shares selling at $50, Romney at $35 and Giuliani at $12. It appears that Thompson's withdrawal boosted Romney and sunk Giuliani.
Here's a helpful link on all the state's delegate totals and award process.